Is airway remodeling clinically relevant in asthma?

The social and economic impact of asthma is substantial worldwide. Although current therapies targeting both airway inflammation and airway hyperreactivity effectively relieve and prevent symptoms in the majority of patients, some patients experience persistent symptoms and a progressive decline in lung function, described as irreversible or refractory asthma. Indeed, there are many unanswered questions about the role of airway remodeling in asthma. This review addresses several topics of controversy, including whether all patients with asthma demonstrate airway remodeling; the contribution of distinct airway resident cells to the development of remodeling; the role of biomarkers or noninvasive measurements in predicting airway remodeling; and the effectiveness of current therapies on airway remodeling and disease progression.